From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F1E3DEE6457 for ; Fri, 15 Sep 2023 12:57:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235165AbjIOM5c (ORCPT ); Fri, 15 Sep 2023 08:57:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59952 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235074AbjIOM5a (ORCPT ); Fri, 15 Sep 2023 08:57:30 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D419DA8; Fri, 15 Sep 2023 05:57:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1694782645; x=1726318645; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=AHr0t4Sal2ucwSsHwruU8cvNvmrzYdJZAc7YNJHAzt4=; b=UmeE0O3uv2IwFAk5IZ7gVLMmsjnj8xDlJyHOpSU+b2WbmoLRfQaxODLI UBroCMRFpEpnznRG/XIIjo4D34CP6ttNAIohadHvxImwdJjzvUYTuW6y7 EqWX6sNlcaKVlW0khSIboSanNnL2zAjp/kzdNitHtxsFA2EryZcnNfO8K A2qBOonVd4KSrO55HTAwsXLqIeBPOhfnl3/xVa099yoeeZ8DSJs4Xaa5F r+9jdOhOiIIq/NLm2JgP4QfBV3vxZAPu1firgDKY377eVA/6arxZtmDX9 aeuSQOT3WEeve19d3NJbtBTnQw9AI8EwNyPCcjeGHqjhj1V5UWUrNrR8i w==; X-IronPort-AV: E=McAfee;i="6600,9927,10834"; a="369558289" X-IronPort-AV: E=Sophos;i="6.02,149,1688454000"; d="scan'208";a="369558289" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Sep 2023 05:57:25 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10834"; a="748195802" X-IronPort-AV: E=Sophos;i="6.02,149,1688454000"; d="scan'208";a="748195802" Received: from kuha.fi.intel.com ([10.237.72.185]) by fmsmga007.fm.intel.com with SMTP; 15 Sep 2023 05:57:21 -0700 Received: by kuha.fi.intel.com (sSMTP sendmail emulation); Fri, 15 Sep 2023 15:57:20 +0300 Date: Fri, 15 Sep 2023 15:57:20 +0300 From: Heikki Krogerus To: Javier Carrasco Cc: Greg Kroah-Hartman , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Bryan O'Donoghue , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Subject: Re: [PATCH v2 1/2] usb: typec: tps6598x: add reset gpio support Message-ID: References: <20230912-topic-tps6598x_reset-v2-0-02a12e2ec50a@wolfvision.net> <20230912-topic-tps6598x_reset-v2-1-02a12e2ec50a@wolfvision.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230912-topic-tps6598x_reset-v2-1-02a12e2ec50a@wolfvision.net> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 15, 2023 at 02:23:48PM +0200, Javier Carrasco wrote: > The TPS6598x PD controller provides an active-high hardware reset input > that reinitializes all device settings. If it is not grounded by > design, the driver must be able to de-assert it in order to initialize > the device. > > The PD controller is not ready for registration right after the reset > de-assertion and a delay must be introduced in that case. According to > TI, the delay can reach up to 1000 ms [1], which is in line with the > experimental results obtained with a TPS65987D. > > Add a GPIO descriptor for the reset signal and basic reset management > for initialization and suspend/resume. > > [1] https://e2e.ti.com/support/power-management-group/power-management/ > f/power-management-forum/1269856/tps65987d-tps65987d-reset-de-assert- > to-normal-operation/4809389#4809389 > > Signed-off-by: Javier Carrasco > Reviewed-by: Bryan O'Donoghue > --- > drivers/usb/typec/tipd/core.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/drivers/usb/typec/tipd/core.c b/drivers/usb/typec/tipd/core.c > index 37b56ce75f39..3068ef300073 100644 > --- a/drivers/usb/typec/tipd/core.c > +++ b/drivers/usb/typec/tipd/core.c > @@ -8,6 +8,7 @@ > > #include > #include > +#include > #include > #include > #include > @@ -43,6 +44,9 @@ > /* TPS_REG_SYSTEM_CONF bits */ > #define TPS_SYSCONF_PORTINFO(c) ((c) & 7) > > +/* reset de-assertion to ready for operation */ > +#define SETUP_MS 1000 > + > enum { > TPS_PORTINFO_SINK, > TPS_PORTINFO_SINK_ACCESSORY, > @@ -86,6 +90,7 @@ struct tps6598x { > struct mutex lock; /* device lock */ > u8 i2c_protocol:1; > > + struct gpio_desc *reset; > struct typec_port *port; > struct typec_partner *partner; > struct usb_pd_identity partner_identity; > @@ -717,6 +722,13 @@ static int tps6598x_probe(struct i2c_client *client) > mutex_init(&tps->lock); > tps->dev = &client->dev; > > + tps->reset = devm_gpiod_get_optional(tps->dev, "reset", GPIOD_OUT_LOW); > + if (IS_ERR(tps->reset)) > + return dev_err_probe(tps->dev, PTR_ERR(tps->reset), > + "failed to get reset GPIO\n"); > + if (tps->reset) > + msleep(SETUP_MS); > + > tps->regmap = devm_regmap_init_i2c(client, &tps6598x_regmap_config); > if (IS_ERR(tps->regmap)) > return PTR_ERR(tps->regmap); > @@ -892,6 +904,9 @@ static void tps6598x_remove(struct i2c_client *client) > tps6598x_disconnect(tps, 0); > typec_unregister_port(tps->port); > usb_role_switch_put(tps->role_sw); > + > + if (tps->reset) > + gpiod_set_value_cansleep(tps->reset, 1); Do you need that "if (tps->reset)" in this case? That function is NULL safe, right? > } > > static int __maybe_unused tps6598x_suspend(struct device *dev) > @@ -902,6 +917,8 @@ static int __maybe_unused tps6598x_suspend(struct device *dev) > if (tps->wakeup) { > disable_irq(client->irq); > enable_irq_wake(client->irq); > + } else if (tps->reset) { > + gpiod_set_value_cansleep(tps->reset, 1); > } > > if (!client->irq) > @@ -918,6 +935,9 @@ static int __maybe_unused tps6598x_resume(struct device *dev) > if (tps->wakeup) { > disable_irq_wake(client->irq); > enable_irq(client->irq); > + } else if (tps->reset) { > + gpiod_set_value_cansleep(tps->reset, 0); > + msleep(SETUP_MS); > } > > if (!client->irq) > > -- > 2.39.2 thanks, -- heikki